Fig. 5. Both sqd and PKA-C1 mutants display ectopic Osk protein localization. (A,B) Osk protein (green) is detectable only at the posterior of wild-type stage 9 oocytes (A). By contrast, Osk protein is seen in some sqd^j4B4 germline clone oocytes mislocalized away from the posterior (B). (C,D) Expression of a lacZ reporter for osk translation, m1⁴¹⁴lacwt (blue), is limited to the posterior pole of stage 9 and older wild-type oocytes (C, arrow); it is not expressed in younger wild-type oocytes (arrowhead). In sqd^j4B4 germline clones, expression of m1⁴¹⁴lacwt is detected in the middle of stage 9 oocytes (D, arrow), although it is never expressed earlier (arrowhead). (E,F) Ectopic Osk protein (green) is seen in the middle of some oocytes that are homozygous for a PKA-C1 null allele (E) or for both sqd^j4B4 and a PKA-C1 null (F). Lack of GFP (red) in the germline marks the PKA-C1 homozygote in (F).